Cantankerous tycoon John P. Merrick (Charles Coburn) goes undercover as a shoe clerk at his own New York City department store to identify agitators trying to form a union, after seeing a newspaper picture of his employees hanging him in effigy. He befriends fellow clerk Mary Jones (Jean Arthur) and her recently fired boyfriend Joe O'Brien (Robert Cummings), a labor union organizer. Through his firsthand experiences, he grows more sympathetic to the needs of his workers, while finding unexpected love with sweet-natured clerk Elizabeth Ellis (Spring Byington).